Electric switch.



W. M. SUOTT.

ELEGTRIG SWITCH.

summon FILED 0019, 1909.

Patented Nov. 1,1910.

To all whom it may concern:

"UNITED STATES PATENT OFFICE.

WILLIAM M, SCOTT, F PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO THE CUTTER ELECTRICAL AND MANUFACTURING COMPANY, A CORPORATION OF NEW JERSEY.

ELECTRIC swr'r'cn.

Specification of Letters Patent.

Application filed October 9, 1909. Serial No. 521,894.

Patented Nov. 1, 1910.

' Be it known that I, WILLIAM M. Soon, a citizen of the United States, residing in the city of Philadelphia, county of Philadelphia, and State of Pennsylvania, have invented a new and useful Electric Switch, of which the following is a specification.

My invention relates to electrical switches suitable for making and breaking or controlling an electric circuit carrying currents of great volume and of considerable potential, and my invention relates more particularly to the relation between the main and shunt contacts, the latter to relieve the, main contacts of the eltects of arcing, and to the means for operating the main and shunt contacts.

My invention resides in an electrical switch or circuit breaker comprising main and shuntmembers, the main and shunt members being pivotally mounted and movable independently of each other, the main contact being operated by any suitable means, such as a toggle, while'the member or arm supporting the shunt contact is cam operated, the cam being preferably operated by oneof the toggle members.

My invention resides in the features here inat'ter described and claimed. 7 For an illustration of one of the forms my invention may take, reference is to be had to the accompanying drawing, in which:

Figure 1 is a side elevational view of an automatic circuit, breaker involving my in-' vention. Fig. 2 is a horizontal sectional View of the main and shunt members and their operating means taken on the line X--X in Fig. 1 and looking in the direction of the arrows, some parts being shown in plan. Fig. 3 is a side elevational view of the shunt contact carrying arm or lever. Fig. 4 is a fragmentary view illustrating a modified form of construction for operating the shunt carrying arm.

In the drawing, 1 represents a base of any suitable insulating material, such as marble, upon which is secured by stud 2 and nut 3 the upper main contact block or terminal 4. Below the terminal or contact 4 is secured the other main terminal or contact 5. 558- cd upon and in electrical communication 'ppcr terminal block 4 is the me t 6 upon which is secured the constituting a main movable contact.

sions of the latch 24 to limit its movement. Pivoted concentrically with thestationary carbon shunt piece 7. Between the bracket 6 and the contact block 4 is secured the intermediate stationary metallic shunt contact 8.

- Adapted to engage and brid e the main terminals 4 and 5, and thereby c ose the circuit, is the laminated bridging member 9, The contact member 9 is secured to, but preferably insulated from, the pivoted arm or lever 10 supported upon the pivot 11 supported in thehousing or bracket 12, shown broken away for the sake of clearness. Supported with or carried by the main movable contact 9 is the intermediate metallic shunt contact 13 secured upon the conducting springs 14 which, in turn, are secured upon the member 15, the latter serving also as a shunt circuit connector. The intermediate shunt. contact 13 is adapted to engage the intcrmediate stationary shunt contact 8.

For actuating the movable member 9 to cramp the same into engagement with the terminal blocks 4 and 5, there is provided a toggle comprising the links 16 and 17, the

former pivoted at 18 to the arm or lever 10 and at 19 to the link 17, the link 17 being pivoted in the housing or bracket 12 at 20 and extending outwardly beyond the housing to form an operating lever 21 provided with the hand grip 22. the position shown in Fig. 1, the center of pivot 19 falls a little short of astraight line drawn through the centers of pivots 18 and 20. Carried by the lever 21 is a roller 23 with which is ada ted to engage the latch 24 pivoted to the casing 12 at 25. vA in 26 carried by the housing 12 is dispose between two rearward extenpivotal latch 24 on the member 25 is the latch actuating member 27 carrying the adjustable screw 28 which enga es u on the top of the latch-24 t'o'actuate it. he latch actuator '27 has a rearwardly extending tail 29 extending into the path of travel of the armature-30, pivoted at 31, and adapted to be attracted by the pole pieces 32 attached to the core 33 of an electromagnet whose energizing coil or winding is the conducting bar S lhaving one end in communication Witt the main terminal 5 and, if desired, formi gthe active contact face thereof; the other end is in electrical communication with the block 35 secured by stud 36 and nut 37 to the base 1. The main path of the current through the instrument is then from stud 2 to main terminal 4, through the bridge 9, t. the lower terminal 5, through winding or bar 34, to block 35, and out by stud 36. A handle 38 is attached to the armature 30 for manually tripping the switch or breaker, and the adjuster 39 is provided for determining the position of the armature 30 with respect to the pole pieces 32, so that the breaker may be set to open at different current loads.

At 40, upon the link 17, is secured one end of a helical tension spring 41, whose other end is secured at 42 to the arm or lever 10. The arm or lever 43 carries the movable shunt carbon piece 44, adapted to en gage the stationary carbon 7, and is secured to the arm or lever 43 by the conducting bracket or member 45. The arm 43 is pivoted, preferably concentrically witlrarm 10, upon the pivot 11. The shunt carbon 44 is supported on, but insulated from, the arm 43, electrical connection being made from the carbon 44 by the flexible connector 46 with the member 15 which also supports the intermediate shunt contact 13,the conductor 15 being extended by a flexible conductor 47 below and around the pivot 11, and connects permanently to the lower main terminal 5.

Upon the toggle'pivot pin 19, or upon a pivot pin carried by link 17 or other memher, is mounted a roller 48 which engages the cam surface 49 formed upon the arm or lever 43. The arm or lever 43 is movable independently of the arm 10. And. the cam surface 49 is of such length and curvature that the toggle 16, 17 may collapse a considerable distance and yet the roller 48 will continue upon the surface 49 holding the lever 43 in the position shown in Fig. 1, until the main movable contact 9 and the intermediate contact 13 have become well separated from their cooperating stationary contacts.

The operation is as follows: \Vhen the armature 30 is lifted. either by handle 38, or by magnetic attraction. it strikes the under side of the tail 29 of the latch actuating, member 27, causing the screw 23 to strike upon the top of the latch 24 and to depress the same. and release the roller 23 to unlock the breaker. The spring 41 is then free to contract, and in doing so knees or collapses the toggle 1G. 17 downwardh and pulls outwardly on the arm 10 carrying the laminated contact 9. The laminated contact 9 then separates from the main terminals 4 and 5. and later the intermediate shunt contact 13 separates from its companion 8. During this movement the lever 43 is held in the position shown in Fig. 1 by the roller 48 continuing its engagement on the upper part of cam surface 49 maintaining that surface at the same distance from the pivot 20. As the collapse of the toggle progresses, however, the roller 48 rolls down the surface 49 and the arm 43 is then free to move out wardly away from the base. The arm 10 in its further movement (after roller 48 has passed off that part of the surface 49 having 10 as a center) carries arm 43 with it away from the base, causing carbon -14 to separate from carbon 7, thus finally breaking the circuit, the final are taking place between the carbons 44 and T. The. movement continues until the full open circuit position is reached by which time the circuit is completely and safely interrupted.

To close the switch, the lever '21, which has been raised in the opening movement, is depressed by an operator. extending the toggle 16, 17 and moving the contact 9 toward the terminals 4 and 5. As the movement progresses the roller 48 rolls upon the cam surface on the member 43, proceeding up its back, and forces the same inwardly toward the base, the carbon 44 engaging the carbon 7 before the intermediate shunt contact 13 engages its companion S, and before the contact 9 engages terminals 4 and 5. As the movement progresses the carbon 44 pressed firmly against carbon 7 and after they are in firm engagement the roller continues along the surface 4.) without further inward movement of the lever 43. But during this continued movement of the toggle, while the lever 43 is stationary, the intermediate shuntcontact- 13 engages its companion 8, and shortly thereafter the contact 9 engages terminals 4 and 5 and is cramped firmly against them, the parts being again in the positions shown in Fig. 1, with the toggle just short of full extension.

While I have shown my invention as applied to an overload circuit breaker, it is to be understood that it is of general application in the art of electric switches. and that it may be applied to circuit breakers which are tripped upon any predetermined electrical condition other than overload.

lVhile I have shown the cam surface upon the arm 43 and the member for engaging the cam surface as carried by the toggle, it is to be understood that their relations may be reversed and that the cam surface may be carried by the toggle. This is illustrated in Fig. 4, where the roller 49 is carried by the shunt arm 43 while the cam surface 48 is carried by or movable with the toggle link 17, (not shown for the sake of elearness) which is pivoted at 20 to the housing 12.

\Vhat I claim is:

1. In an electric switch. movable main and shunt contacts, an arm carrying a shunt contact independently of said main contact,

members'pivoted to each other for operatvertically QXtQINlJII pivoted arm carrying ing said main contact, a cam surface on said shunt carrying arm, and a cam engaging member carried at the pivotal connection ot said members for operating said shunt car rying ,arm.

In an electric switch, movable main an shunt contacts,-an arm carrying a shunt contact; independently of said main contact,

and'shunt contacts. a pivoted arm supportlinks pivoted to each other to form a toggle for operating said main contact, a cam surface on said shunt carrying arm, and a cam engaging member carried by the pivot joining sait toggle links for operating said shunt carrying arm.

3. In an electric switch, movable main and shunt contacts, an arm carrying a shunt contactindependently of said main contact, j

links pivoted to each other to form a toggle for operating said main contact, a cam surface on said shunt carrying arm, and a cam engaging member carried at the pivot joincrating pivoted arm supporting a main contact, a

vertically extending arm carrying a shunt contact pivoted concentrically with .but independently of said main contact arm, a

pivoted lever for operating said main contact arm, a cam surface on said shunt contact arm, and a cam engaging member carried by said pivoted operating lever intermediate the pivot of said operating lever and its connection with said main contact ing said toggle links, the surface of said cam engaged by said cam engaging member at approximately and full C1ICu1t (!l0S1I1g posi- 't1on being determined by an are having a pivot of a. link of said toggle as a center.

4. In an electric switch, movable main and shunt contacts, an arm carrying a shunt contact independently of said main contact, 5

members pivoted to each other for operating said inain contact, a cam surface on said hunt carrying arm, and a cam engaging shunt carrying arm. and a cam engaging;

bers intermediate the ternnnal pivots of said member carried by one of said pivoted members intermediate the terminal pivots of said i and shunt contacts, a vertically extending tact pivoted independently of but concentrically with said main contact arm, members pivoted to each other foroperating said main contact arm, a cam surface on said member carried by one of said pivoted ineinmembers.

11. In an electric switch, movable main and shunt contacts, a vertically extending links pivoted to each other to form a toggle for operating said main contact, a cam surface on said shunt carrying arm. and a cam engaging member carried by said toggle intermediate the terminal pivots of said toggle.

6. In airelectric switch. movable main ing a main contact, a pivoted arm carrying a shunt contact. members pivoted to each other for operating said main contact arm, a cam surface on said shunt carrying arm, and a cam engaging member carried by one of said pivoted members intermediate the 1 intermediate the terminal pivots 0f,sa1d toggle. the portion of said ca'in. surface enterminal pivots of said members.

7. In an electric switch. mo 'ablem'am and shunt contacts. a pivoted arm carrying proxnnately and full circuit closing position arm carrying a shunt contact, links pivoted a main. contact. an independently pivoted ing member carried by said toggleinterme,

(hate the terminal pivots of said toggle.

8. In an electric switch. movable main and shunt contacts, a verticallyextending pivoted arm carrying a main contact, a ver-.

10. In an electric switch, movable main tically extending arm carrying a shunt contact pivoted independently of but concentrically with said main contact arm, links pivoted to each other to form a toggle for operating said main contact, a cam surface onsaid shunt carrying arm. and a cam engaging member carried by said toggle intermediate the terminal pivots of said toggle.

1; In an electric switch, movable main and. shunt-contacts,an arm carrying a shunt contact independently of said main contact,

links pivoted to each other to form a toggle for operating said main contact, a cam surface on said shunt carrying arm, and a cam engaging member supported by said toggle gaged bv said cam engaging member-at apcontact independently of said main contact, links pivoted to eachother to form a toggle for operating saidinain contact, a cam surface on said shunt carrying arm, a rQlJerfor V engaging said cam surface carried by said toggle intermediate the terminal pivots of said'toggle; i

14, In an electric switch, movable main and shunt contacts, a pivoted arm carrying a main contact, an independently movable pivoted arm carrying a shunt contact, links pivoted to each other to form a toggle for operating said main Contact arm, a cam surface on said shunt carrying arm, and a cam m c r mber carried by said toggle i l l i l i intermediate the stationary toggle pivot and the pivotal connection of a toggle link with said main contact arin.

In testimony whereof I have hereunto aflixed my signature in the presence of the two subscribing witnesses.

\VILLIAM M. SCOTT.

lVitnesses i lnnimon T. MCCALL, ANNA E. STEINBOGK. 

